We’ve also added subtitles to the ‘How to’ video. To access these, click the caption icon and select your language. The majority of the users of Learn Chemistry are based outside the UK, and these translations are one way that we’re working to support our international users.

If you speak any of these languages, or know someone who does, please spread the word – we’re keen to get as many international participants as we can.

YouTube isn’t available in China, so our team in China have added the video to YouKu, the Chinese equivalent, complete with a voiceover. Here’s Lee speaking Mandarin!